Officials say the sugarcane aphid has returned to Kansas.

The Wichita Eagle reports that the tiny Southern pests have threatened grain sorghum, or milo, fields in the Sunflower State the previous two years. Kansas is the nation’s leading producer of grain sorghum.

Aphids were reported and confirmed in fields in Sumner and Cowley counties this week.

Officials are scouting fields but haven’t determined how far north the aphids have spread.

Last year, some sorghum producers saw heavy yield losses due to sugarcane aphids. Kansas State University says the pest spread to 36 Kansas counties, making it close to the Nebraska border.